I have to admit that I find Teradata strategy to let customer pay for new feature information like Teradata 15.0 JSON Integration very odd.
But beside this a usually start with the release notes of Relase 15.0 this is always recommended.
I guess after partners 2014 you might see some more public available slides.

Just to name a few:
we can write codes in any language and execute using SCRIPT,table operator,Ferret showblocks sql interface,
Table operator enhancements,TASM enhancements,DBQL logs stats for DSA,IN clause parameter upto 1 MB
z-coordinate for 3D introduced, ANSI temporal syntax feature support and AJI for Temporal,DBC.DBQLParamTbl for parameterized queries,
Performance improvements in DIP,Geospatial, JSON, GEOJSON when dealing with UDA
and few more.
Heard that querygrid is also coming up in future release.

Raja K Thaw
My wiki: http://en.wikipedia.org/wiki/User:Kt_raj1
Street Children suffer not by their fault. We can help them if we want.

Thank you very much for your response. When I know more, my curiosity forcing me to ask a couple of questions more.
Which are the new licenced features. I have seen that the Teradata Columner is a licensed package with TD 14. Similarly, the incremental backups too are separate licence. Any enhanced features are there those are licensed?